Due to employee safety negligence at a nuclear waste facility, 2000 tons of a radioactive element is spilled into the nearby pond. The half-life of the radioactive element is 36 days. In order to be declared safe for swimming, based on its size and the amount of water, there must be less than 100 tons of the material found in the pond. How long, to the nearest day, until it is safe to swim again?

Given:

The function are:

[tex]f(x)=Kx^2+4x-3[/tex]

[tex]g(x)=2x-7[/tex]

The graph of f(x) intersect the line g(x) at one point.

To find:

The value of K.

Solution:

The graph of f(x) intersect the line g(x) at one point. It means the line g(x) is the tangent line.

We have,

[tex]f(x)=Kx^2+4x-3[/tex]

Differentiate this function with respect to x.

[tex]f'(x)=K(2x)+4(1)-(0)[/tex]

[tex]f'(x)=2Kx+4[/tex]

Let the point of tangency is [tex](x_0,y_0)[/tex]. So, the slope of the tangent line is:

[tex][f'(x)]_{(x_0,y_0)}=2Kx_0+4[/tex]

On comparing [tex]g(x)=2x-7[/tex] with slope-intercept form, we get

[tex]m=2[/tex]

So, the slope of the tangent line is 2.

[tex]2Kx_0+4=2[/tex]

[tex]2Kx_0=2-4[/tex]

[tex]x_0=\dfrac{-2}{2K}[/tex]

[tex]x_0=-\dfrac{1}{K}[/tex]

Putting [tex]x=x_0,g(x)=y_0[/tex] in g(x), we get

[tex]y_0=2x_0-7[/tex]

Putting [tex]x=-\dfrac{1}{K}[/tex] in the above equation, we get

[tex]y_0=2(-\dfrac{1}{K})-7[/tex]

[tex]y_0=-\dfrac{2}{K}-7[/tex]

Putting [tex]x=-\dfrac{1}{K}[/tex] and [tex]f(x)=-\dfrac{2}{K}-7[/tex] in f(x).

[tex]-\dfrac{2}{K}-7=K\left(-\dfrac{1}{K}\right)^2+4(-\dfrac{1}{K})-3[/tex]

[tex]-\dfrac{2}{K}-7=\dfrac{1}{K}-\dfrac{4}{K}-3[/tex]

[tex]-\dfrac{2}{K}-7=\dfrac{-3}{K}-3[/tex]

Multiply both sides by K.

[tex]-2-7K=-3-3K[/tex]

[tex]-2+3=7K-3k[/tex]

[tex]1=4k[/tex]

[tex]\dfrac{1}{4}=K[/tex]

Therefore, the value of K is [tex]\dfrac{1}{4}[/tex].

Answer:

2520 ways

Step-by-step explanation:

Given

[tex]n = 10[/tex]

[tex]r = (2,3,5)[/tex]

Required

The number of selection

First, select 2 people from 10 in 10C2 ways.

There are 8 people, left.

Next, select 3 people from 8 in 8C3 ways.

There are 5 people left.

Lastly, select 5 from 5 in 5C5 ways

So, we have:

[tex]Total = ^{10}C_2 * ^8C_3 * ^5C_5[/tex]

Using combination formula

[tex]Total = 45 * 56 * 1[/tex]

[tex]Total = 2520[/tex]

Factorize the numerator:

4r + 20 = 4r + 4×5 = 4 (r + 5)

I think you meant to say r ≠ -5, which means r + 5 ≠ 0, so that the denominator is never zero and so the expression is defined (no division by zero). This lets you cancel the factor of r + 5 in the numerator with the one in the denominator:

(4r + 20)/(r + 5) = 4 (r + 5)/(r + 5) = 4

Step-by-step explanation:

The iso parts of isometric means same, and It is similar becuase rigid trtransformation and the metric parts means measure. Basically isometric means same measure. Rigid transformation preserve "same measures" like angles and side lengths.

[tex] \cos(45) = \frac{5 \sqrt{2} }{x} \\ \frac{1}{ \sqrt{2} } = \frac{5 \sqrt{2} }{x} \\ x = 10 \\ \\ \tan(45) = \frac{y}{5 \sqrt{2} } \\ 1 = \frac{y}{5 \sqrt{2} } \\ y = 5 \sqrt{2} [/tex]

I hope I helped you ^_^

Answer:

12 miles

Step-by-step explanation:

1/3 of an hour = 20 minutes = 4 miles

1 minute = 4/20 miles

60 minutes = 4/20 x 60 miles

                   = 4 x 3 miles

                   = 12 miles

60 minutes = 1 hour

=> 1 hour = 12 miles

Jacks unit rate is 12 miles/hr

Answer:

12

Step-by-step explanation:

There are two ways of doing this problem. I think the easiest way is to use a decimal in the denominator and round

4/0.333333333 = 12.000000001

The answer is obviously meant to be 12.

The other way is more sophisticated, but more accurate.

4/1 // 1/3               This is a 4 tier fraction. The rule is to invert the denominator (turn the bottom fraction upside down) and multiply.

4/1 * 3/1 = 12

The first method is easier to understand. The second is more accurate and more useful for physics.

Answer:

A) 89 personas prefieren ver sólo deportes.

B) 122 personas prefieren ver sólo un programa de televisión

C) 33 personas prefieren ver películas o musicales.

Step-by-step explanation:

Dado que una empresa realizó una encuesta a 250 personas para saber qué programa de televisión prefieren ver en domingo, y se les dieron 3 opciones: deportes, películas o musicales, donde el resultado de la encuesta fue: 130 personas prefieren deportes; 80 prefieren ver películas; 40, musicales; 25 prefieren deportes y películas; 20, películas y musicales; 10, deportes y musicales; y sólo a 6 personas les gustan los tres tipos de programas; para determinar A) cuántas prefieren ver sólo deportes, B) cuántas prefieren ver sólo un programa de televisión; y C) cuántas prefieren ver películas o musicales, se deben realizar los siguientes cálculos:

A)

130 - 25 - 10 - 6 = 89

B)

80 - 25 - 20 - 6 = 29

40 - 20 - 10 - 6 = 4

89 + 29 + 4 = 122

C)

29 + 4 = 33

Answer:

-7/5

Step-by-step explanation:

I think let me know

Answer:

7/-5  or -7/5

Step-by-step explanation:

This shall be quite an easy problem, I shall be doubting that this is high school, however, I am happy to aid :)

We shall begin by labeling the points given to us to prepare for inputting the values in the slope formula

(3,4).     (8,-3)

x1,y1     x2,y2

Slope Formula:

y1 - y2

x1 - x2

Inputting the values:

4 - (-3)

3 - 8

Solve:

7

-5

The slope of the line passing through the points (3,4) and (8,-3) shall be 7/-5 or -7/5 negatives shall go both ways of fractions

Answer:

Step-by-step explanation:

you can use the rise over run technique, where you count how many units you go down or up, left or right to get to the next point. or use the slope formula :

(y2-y1)/(x2-x1)

the pairs given :

(1,6) and (3,2)

(2-6)/(3-1) = -4/2 = -2

-2 is the slope. the line is going downwards so there is a negative slope

9514 1404 393

Answer:

  ₹1442

Step-by-step explanation:

The new price will be 1+3% = 1.03 times the old price.

  ₹1400 × 1.03 = ₹1442

Answer:

2x+3x=90

or ,5x=90

or,x=90/5

X=18

Answer:

90/5=18 degrees

Step-by-step explanation:

the answer would be 5 because 5*5 or 5 squared (5^2) is equal to 25, hope this helps!

Answer:

The 2nd one is 3x+1

The 3rd answer is x+3

Step-by-step explanation:

Given g(x)=4x-1 and f(x)=x-2

Subtracting both

4x-1-(x-2)=4x-1-x+2=x(4-1)+(2-1)=3x+1

The next one is 3x+1-(2x-2)=3x+1-2x+2=x+3

B. x = 5

tip : if in a rush just plug in the number and see if its true

8x - 4 = 36

x = 5

Answer:

[tex]\displaystyle d = \sqrt{29}[/tex]

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Algebra I

Algebra II

Step-by-step explanation:

*Note:

The distance formula is derived from the Pythagorean Theorem.

Step 1: Define

Identify

Point (5, 10)

Point (10, 12)

Step 2: Find distance d

Hi there!  

»»————-　★　————-««

I believe your answer is:  

[tex]x = -5[/tex]

»»————-　★　————-««  

Here’s why:  

⸻⸻⸻⸻

[tex]\boxed{\text{Solving for 'x'...}}\\\\3(x+1)=12+4(x-1)\\----------\\\rightarrow 3x + 3 = 12 + 4x - 4\\\\\rightarrow 3x + 3 = 12 -4+4x\\\\\rightarrow 3x + 3 = 8 + 4x\\\\\rightarrow 3x + 3 = 4x + 8\\\\\rightarrow3x + 3 -3 = 4x + 8 - 3\\\\\rightarrow 3x = 4x + 5\\\\\rightarrow 3x - 4x = 4x - 4x + 5\\\\\rightarrow -x = 5\\\\\rightarrow \frac{-x=5}{-1}\\\\\rightarrow \boxed{x = -5}[/tex]

⸻⸻⸻⸻

»»————-　★　————-««  

Hope this helps you. I apologize if it’s incorrect.  

Answer:

Step-by-step explanation:

3(x+1)=12+4(x-1)

3(x+1)=8+4x

3x+3=8+4x

3x+3−4x=8

-x+3=8

-x=8-3

-x=5

-x(-1)=5(-1)

-x(-1)=-5

x=-5

Answer:

15/2 that is the answer man

Answer: £21007.22

Step-by-step explanation:

First, find the interest amount using the formula SI = (P × R × T) / 100.

SI = (P × R × T) / 100 = (18790 × 5.9 × 2)/100 = 221722/100 = £2217.22

The total amount = principle amount + interest amount

= £18790 + £2217.22 = £21007.22

Answer:

TE = 7

Step-by-step explanation:

The centroid divides a median in this ratios 1/3 and 2/3. In particular

XT = 2/3 XE

XT = 2/3 * 21

XT = 14

TE = 7

Answer:

Step-by-step explanation:

This is most easily solved with calculus, believe it or not. It is way more direct and to the point, with a whole lot less math!

The position function is given. The velocity function is the first derivative of the position, so if we find the velocity function and set it equal to 0, we can solve for the amount of time it takes for the rocket to reach its max height. Remember from physics that at the top of a parabolic path, the velocity is 0.

If:

[tex]s(t)=-16t^2+112t+360[/tex], then the velocity function, the first derivative is:

v(t) = -32t + 112 and solve for t:

-112 = -32t so

t = 3.5 seconds. Now we know how long it takes to get to the max height, we just need to find out what the max height is.

Go back to the position function and sub in 3.5 for t to tell us that position of the rocket at 3.5 seconds, which translates to the max height:

[tex]s(3.5)=-16(3.5)^2+112(3.5)+360[/tex] and

s(3.5) = 206 feet. I imagine that your answer, if you had to choose one from the list, would be 200 feet, rounded a lot.

Answer:

Equation:  [tex]70=(x+3)x[/tex]

x = -10 or x = 7

x = 7 (width can't be negative)

x + 3 = 10

Step-by-step explanation:

Represent the width of the rectangle by  x.  "The length of a rectangle EXCEEDS the width by 3" means the length is 3 LONGER than the width, so the length is represented by the expression  x + 3.

Area = (length)(width)

70 = (x + 3)x

Multiply out the right side.

[tex]70=x^2+3x\\x^2+3x-70=0[/tex]

Factor the left side.

[tex](x+10)(x-7)=0[/tex]

Each binomial could equal 0, so

[tex]x+10=0 \text{ or }x-7=0\\x=-10\text{ or }x=7[/tex]

The negative solution does not make sense as the width of a rectangle.

x = 7, making the length, x + 3 = 10

Answer:

Pls mark this as brainiest

Step-by-step explanation:

Area of the rectangle = length x breadth

consider 'x' to be width

therefore length = x+3

area = (x+3)*x

Area = 70 square

x = 7

x+3 = 7+3

      = 10

verification

7 x 10

= 70

Answer:

Step-by-step explanation:

The percents here make this more tricky than it originally seems to be. We'll make a table and see where it takes us:

                          original                 new

length

width

And we'll fill it in according to our rules given. Starting with the original, we are told that the width is twice as long as the length. We don't know the length, so we'll call that L, and if the width is twice that, the width is 2L:

                           original                  new

length                       L

width                       2L

Now here's the tricky part. What I'm going to do is fill in the "new" column with the expressions and then we'll simplify them in the next step.

The length is increased by 50%. So we have 100% of the original length and we are adding another 50% to that:

                            original                        new

length                      L                       100%L + 50%L

width                       2L

The width is decreased by 20%, so we have 100% of 2L and we are subtracting 20% of 2L from that:

                             original                       new

length                        L                     100%L + 50%L

width                        2L                  100%(2L) - 20%(2L)

And now we'll simplify that "new" column:

                              original                         new

length                        L                         150%L = 1.5L

width                         2L               80%(2L) = 160%L = 1.6L

Now we're ready for the perimeter part. The formula for the perimeter of a rectangle is P = 2L + 2w, so filling in from our "new" column, since 248 is the perimeter given for AFTER the rectangle's length and width are manipulated:

248 = 2(1.5L) + 2(1.6L) and

248 = 3L + 3.2L and

248 = 6.2L so

L = 40 and that means that w = 80 (because in the "original" column, the width is twice the length)

Answer:

[tex] {x}^{2} - 7x + 4x - 28 \\ = x(x - 7) + 4(x - 7) \\ = (x - 7)(x + 4)[/tex]

Answer:

84%

Step-by-step explanation:

I'm not sure how I got that answer but I'm just smart like that. I'm sorry I couldn't give a better explanation. I'm in a bit of a rush but I hope this answer is helpful to you. Percentage was the only way I could think of. Sorry again.

The difference between  CDs sold between 1993 and 2001 will be 76.7 × 10⁵.

To subtract in mathematics is to take something away from a group or a number of objects.

In another meaning subtraction is a mathematical operation such that two values are going to subtract and give a resultant value.

The group's total number of items decreases or becomes lower when we subtract from it.

Given that sell of CDs in 1993 is 2.3 × 10⁶.

Sell of CDs in 2001 is 7.9 × 10⁷.

The difference between sell is = 7.9 × 10⁷ - 2.3 × 10⁶

⇒ 76.7 × 10⁵ hence it will the correct option.

For more about subtraction,

https://brainly.com/question/1927340

#SPJ2

Answer:

Step-by-step explanation:

5.1, please this is just a guess from using my head to calculate

Answer:

8 1/4 kg

Step-by-step explanation:

Add the weight of the fruits together

3 1/2 + 4 3/4

Get a common denominator of 4

3 2/4 + 4 3/4

7 5/4

7 4/4 + 1/4

8 1/4 kg

Answer:

56

Step-by-step explanation:

Zoe : hanna

3         7

Zoe got 24

3*8 = 24

so multiply each side by 8

Zoe : hanna

3*8         7*8

24           56

Hanna got 56

Total amount she wants to raise = $3200

Amount she'll get for each kilometer = $35

So, number of kilometers she need to run

= Total amount she wants to raise/Amount she'll get for each kilometer

= $3200/$35

= 91.42....

Since her sponser is will donate only for whole kilometers she'll have to run 92 km.

Answer:

The way I would tackle these types of problems would be to make a table, then graph the points using the results I get.

Step-by-step explanation:

So explaining the table is kinda hard since I suck at explaining, so I've attached a file showing the table I've made for number 1.

First Step:

Make the table. Make it a 3x4 table. For the top row, put y, the equation (I put 'y=2x' as shown in number 1), then x. Then for the left column, go down by one box, then put: -1, 0, 1. Really, you can put any numbers, but to make it easy for yourself, just write the numbers I've listed. These will be your y-values you'll be substituting.

Second Step:

a.) Plugging in the numbers. For the middle column, I've put down y=2x in each box, as shown in my table. Then for each of those boxes, plug in the numbers to the left of them and substitute them for the y-value. For example, look at the second row. The left box has '-1', so I replaced the 'y' in the equation and got '(-1)=2x'.

b.) After substituting the y-values, solve for x. For this case, you'll need to divide both sides by 2. If it doesn't make much sense, think about a seesaw. If you have 5 pounds on both sides, the seesaw will stay balanced. Add an additional 5 pounds to one side, then the seesaw will start tipping towards the heavier sides. So in order to keep an equation balanced, you must do any action to both sides of the equation. After diving both sides by 2, you'll get the value for x.

Final Step:

After finding the x-values for each of the y-values, it's time to graph the equations. Remember, x is left to right and y is down to up. To graph them, let's use the second row for example. y=-1 and x=-0.5. So all you need to do is to start from the origin (0,0), then go half a unit to the left, as x is negative, then go a unit down, as y is negative, then make a point. The rest should be pretty straight forward.

After making all three points, just get a ruler or any straight edge, then align it along those three points, then just make a line, and boom! You've solved number 1! For the purpose of saving my time, I'm pretty sure you can solve the rest using what I've just told you. Good luck!

Answer:

Step-by-step explanation:

the answer is a)